Hydromys chrysogaster
Silhouette: Rachel T Mason · PhyloPic
In 3 days ~20% in a week ~50%
The rakali (Hydromys chrysogaster), also known as the rabe, the "Australian otter" or water-rat, is an Australian native rodent first scientifically described in 1804. Adoption of the Ngarrindjeri name rakali is intended to foster a positive public attitude by Environment Australia.
One of four described species in the genus Hydromys, it is the only one with a range extending beyond New Guinea. Having adapted to and colonised a unique niche of a semiaquatic and nocturnal lifestyle, this species lives in burrows on the banks of rivers, lakes and estuaries and feeds on aquatic insects, fish, crustaceans, mussels, snails, frogs, cane toads, bird's eggs and small water birds.
Rakali have a body length of 23–37 cm (9–15 in), weigh 340–1,275 g (12–45 oz), and have a thick tail measuring around 24–35 cm (9–14 in). Females are generally smaller than males but tail lengths are normally the same. They have partially webbed hind legs, waterproof fur, a flattened head, a long blunt nose, many whiskers and small ears and eyes. The body is streamlined with a skull that is large, flat and elongated, with two molars on the upper and lower jaw, similar to the water mouse. They are black to brown in colour with an orange to white belly, and dark tail with a white tip.
Long considered a nuisance animal, rakali were hunted for their soft fur, particularly in the Depression of the 1930s, when a ban was placed on imported pelts such as the American muskrat. With their numbers under threat, a protection order was issued in 1938. However, they were still subject to destruction permits from 1938 to 1957 due to their effect on irrigation banks and alleged damage to fishing nets. Additionally, from 1957 to 1967 a number of licensed seasons were also held for this reason. Wikipedia →
Recording1:00
Australia · 2026
© stephenwwalsh · iNaturalist · CC BY-NC 4.0
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Australia · 2024
© lkosack · iNaturalist · CC BY-NC 4.0
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Kosciuszko National Park | 🇦🇺 Australia | |
| 2 | Daintree National Park | 🇦🇺 Australia | |
| 3 | Lamington National Park | 🇦🇺 Australia | |
| 4 | Blue Mountains National Park | 🇦🇺 Australia |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Yerevan Zoo | 🇦🇲 Armenia | |
| 2 | London Zoo | 🇬🇧 United Kingdom | |
| 3 | Frankfurt Zoological Garden | 🇩🇪 Germany |
With luck
About 10% of wildlife watchers report a Rakali sighting in Melbourne on a given day, based on 147 verified sightings from GBIF citizen-science data. It is the 9th most-seen of the 22 mammals we can rate there. Over three days the chance rises to about 20%, and over a week to about 50%, if each day is a fresh chance.
January to November
In those months about 10% of wildlife watchers report a Rakali in Melbourne on a given day, against under 5% in December, the lowest month.
Between 2 and 5 pm
Across all the parks we cover, that three-hour window holds the most Rakali sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Among the best
Of the 3 cities where we can rate Rakali sightings, Melbourne ranks 2nd at about 10%, level with the leaders once rounded. The best odds are in Brisbane (Australia, about 10%).
GBIF citizen-science records
It is estimated from how often the Rakali is recorded against all the mammals logged in Melbourne (147 verified sightings), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
